Genomic sequencing has opened the door to numerous studies that help us understand the evolutionary forces shaping the genetic makeup of organisms. Using databases containing the sequences of 25 genomes, scientists examined the relationship between GC content and global amino acid composition [Kreil, D. P., and Ouzounis, C. A. (2001) Nucl. Acids Res. 29:1608–1615]. They found that it is possible to identify thermophilic species on the basis of their amino acid composition alone, which suggests that evolution in a hot environment selects for a certain whole organism amino acid composition. In what way might evolution in extreme environments influence genome and amino acid composition? How might evolution in extreme environments influence the interpretation of genome sequence data?

Video transcript

Hi, everybody. Let's take a look at this practice problem together if environmental heterogeneity can enhance genetic polymorphism, which of the following habitats can we expect to find high genetic diversity? Is the answer. A grasslands be agricultural areas, sea mangrove forests or d tree plantations. So recall what environmental heterogeneity is and it is the diversity of the environment which can include things like soil, vegetation and climate to name a few. So a habitat with high genetic diversity will have high genetic polymorphism. Therefore, this means it will also have high environmental heterogeneity. So in short, the more biodiversity of an environment, the more genetic diversity. So out of all of our options, they all have biodiversity. However, mangrove forests have the most. So the correct answers options see now mangrove forests are highly complex environments and that's because they have frequent changes in their environment and also their environment straddles both land and sea. So the correct answer is option c Alright, everyone. I hope you found this helpful and I'll see you soon for the next practice problem.